The present invention relates to a compressed gas-insulated bus between a metal-enclosed, compressed gas-insulated high-voltage switching installation and a transformer, which contains in one embodiment a compensator and in which the bus is connected on one side to a bus connection of the metal-enclosed, compressed gas-insulated high-voltage switching installation and on the other side to a transformer connection.
Such compressed gas-insulated buses are common and are known, for example, from EP No. 0 055 094 B1. In these buses, a conductor is disposed inside a typically cylindrical housing. Between the housing and the conductor a compressed insulating gas is provided. The compensator present in the known gas-insulated bus allows a certain range of tolerance for fastening the gas-insulated bus to the adjacent connecting sleeves. This possible range of tolerance depends on the allowable movements, predetermined by the dimension of the compensator, in the direction of its longitudinal axis .+-..DELTA.L and the allowable angular movements .+-..alpha.. The range of tolerance ascertainable by the angular movements is thereby also dependent on the distance L between the compensator and the flange connection used for the gas-insulated bus connection. Thus, the possible tolerance compensation depends primarily on the dimensions of the compensator which is an expensive structural member and has a tendency of buckling easily during large axially allowable movements on account of the large number of required folds or windings, so that only the allowable axial excursion of the compensator can be utilized for the tolerance compensation.
But even in compressed gas-insulated buses without a compensator it is sometimes necessary to provide a compensable range of tolerance for the connecting sleeve of the transformer connection.
To increase operational availability it is a requirement, however, in the event of damage precisely with transformers in electric supply plants and connected to metal-enclosed, compressed gas-insulated high-voltage switching installations, that a transformer be replaced as quickly as possible, for which reason the range of tolerance to be covered with the gas-insulated buses (with or without a compensator) can be very large since the dimensions of the connecting sleeves of the transformer connections can vary.